Power Consumption:

On top of our graphics performance testing, we have also measured the power consumption of Nvidia's GeForce 8800 GTS 512MB graphics card at both idle and load. For this we used a slightly different test system, in order to keep the system the exactly the same across all of our power consumption measurements.

The system was configured as follows:

• Core 2 Duo E6750 (operating at 2.66GHz -- 8x333MHz)
  
• Gigabyte X38-DS5 motherboard (Intel X38 Express)
  
• 2 x 1GB OCZ FlexXLC PC-9200 memory (operating in dual-channel at DDR2-800 with 4-4-4-12 timings)
  
• Seagate Barracuda 7200.9 200GB SATA hard drive
  
• PC Power & Cooling 750W Silencer
  
• Windows Vista Ultimate x86

For our idle testing, we left the systems idling on the desktop for ten minutes, recording the average draw at the wall socket. For load testing, we used our benchmark routine from Crysis in DirectX 10 mode and measured the peak power consumption in this section of the title. We tested the cards in a number of other scenarios and this proved to be the most intensive in all cases, so you can consider this to be a worst-case scenario.

Bear in mind that we have disabled all CPU-related power management options in the motherboard's BIOS so that we can highlight exactly how well the GPU's power management features are working (or not).



TSMC’s 65nm process appears to work wonders for Nvidia on the GeForce 8800 GTS 512, as at idle, it consumes 13W less than the GeForce 8800 GTS 640, while only consuming 7W more than the GeForce 8800 GT. Of course, it’s no match for the Radeon HD 3870 and its awesome power saving technologies in this department, but it’s a long way from being a gas guzzler.

Under load, the card doesn’t do quite as well, as the gap between the GeForce 8800 GTS 512 and its cousin, the GeForce 8800 GT, increases to almost 30W. At the same time, the GeForce 8800 GTS 640 doesn’t consume much more power than the GTS 512, but it doesn’t perform quite as well. What’s impressive is that the card consumes around 40W less than the GeForce 8800 GTX, while maintaining very similar performance characteristics to it in scenarios that aren’t reliant on memory bandwidth.